WO2024212805A1 - Continuous graphitization and purification furnace, and protection device and cooling system therefor - Google Patents

Abstract

Provided in the present invention are a continuous graphitization and purification furnace, and a protection device and a cooling system therefor. Graphitization materials of the continuous graphitization and purification furnace are subjected to three stages of preheating, temperature-rising and exhausting, thermally insulating graphitization, and cooling and discharging when flowing in a bottomless crucible and a cooler, and upper and lower stirring are performed in the crucible, such that continuous production of a graphitization process is achieved; and a stable temperature field is provided in the continuous graphitization and purification furnace, thereby improving the production efficiency and product quality. The self-adaptive protection device, intelligent protection device and cooling system for a graphitization furnace can improve the safety and stability in terms of operation of the graphitization furnace.

Description

A continuous graphitization and purification furnace and its protective device and cooling system Technical Field

The invention relates to the technical field of graphite material manufacturing, in particular to a continuous graphitization and purification furnace and a protective device and a cooling system thereof.

Background Art

The current production of graphite negative electrode materials includes the crushing, drying, fine crushing, coating, granulation, graphitization and other processing processes of raw materials. It is a periodic intermittent operation. The materials after coating and carbonization need to be cooled and then graphitized. The graphitization equipment such as Acheson graphitization furnace, internal string graphitization furnace, graphitization box furnace, etc. cannot be produced continuously. On the one hand, a large amount of heat will be generated in the production process of negative electrode materials and stored in the insulation material, resistor material and furnace refractory material. This heat cannot be effectively reused and is dissipated to the environment when the material is cooled, which not only wastes a lot of energy but also increases the production cost; on the other hand, it takes a long time to cool the material to the discharge temperature to complete the natural cooling of the material in the production process of negative electrode materials, which greatly reduces the production efficiency.

The graphitization furnace is a kind of equipment used in the chemical field, usually used for graphitization of materials such as polyacrylonitrile carbon fiber, further removing nitrogen, oxygen, hydrogen and other elements, and converting the fiber from a chaotic layer structure to a graphite-like structure. The working temperature is as high as 2800℃, the heating rate is greater than 60 degrees per hour, and it is in an inert gas atmosphere with a slight positive pressure of 0.1~0.4MPa. Under normal operating conditions, the furnace body pressure stabilization system can stabilize the pressure in the furnace, but when water leakage or material blockage occurs in the graphitization furnace, the gas pressure in the furnace increases sharply. At this time, the furnace body pressure stabilization system fails, and the high-pressure and high-temperature materials in the furnace urgently need a discharge channel, otherwise it will cause greater risks.

How to improve the safety and stability of the operation of the graphitization furnace cooling system has become a technical problem that needs to be urgently solved by technical personnel in this field.

Summary of the invention

The present invention aims to solve at least one of the deficiencies in the prior art.

The present invention provides a continuous graphitization and purification furnace, comprising:

A vertical furnace body having a cavity inside, and an inert gas pipe communicating with the cavity for providing a protective atmosphere;

A feeding mechanism and an exhaust duct connected to the top of the vertical furnace body;

An induction coil is arranged in the vertical furnace body and extends upward from the bottom of the vertical furnace body, wherein the core of the induction coil is provided with a crucible group consisting of a plurality of coaxial vertically stacked bottomless crucibles, and an insulation layer is provided between the crucible group and the induction coil;

A first driving device is arranged at the top of the vertical furnace body, and a first graphite shaft is drivingly connected to the first driving device, an upper stirring blade is connected to the first graphite shaft, the first graphite shaft extends from the top of the vertical furnace body into the bottomless crucible at the top of the crucible group, and the upper stirring blade is used to stir the material;

A cooler is connected to the discharge port at the bottom end of the vertical furnace body, the bottom of the cooler is connected to a second driving device, the second driving device is transmission-connected to a second graphite shaft, a lower stirring blade is connected to the second graphite shaft, the second graphite shaft extends from the bottom of the cooler into the cooler and extends to the bottomless crucible at the bottom of the crucible group, and the lower stirring blade is used to stir the material;

A discharging mechanism disposed below the cooler;

A number of temperature measuring channels pass through the induction coil and the insulation layer and directly reach the crucible group, and infrared thermometers are provided in the temperature measuring channels.

Based on the above improvement scheme, as a further improvement technical scheme, the upper and lower adjacent bottomless crucibles are connected by a convex stopper and a concave stopper respectively arranged on the two upper and lower adjacent crucibles.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, the thermal insulation layer includes an inner frame body, an intermediate body and an outer thermal insulation body; the inner frame body is made of a three-dimensional needle-punched carbon fiber blank, which is shaped, and a carbon source gas is introduced to perform chemical vapor deposition to increase the density to 1.4g/cm3~1.6g/cm3 to prepare a carbon/carbon composite material, and then the carbon/carbon composite material is graphitized at a temperature of 1800~2500℃ under the protection of an inert gas or nitrogen to obtain the thermal insulation layer; the intermediate body includes at least one layer composed of a plurality of carbon fibers A carbon fiber hard felt layer is spliced by carbon fiber hard felt blocks, the carbon fiber hard felt blocks are composed of several layers of carbon fiber carbon felt and resin is brushed or sprayed between the carbon fiber carbon felt layers for solidification and shaping, and then the formed carbon fiber hard felt is cut into several blocks after carbonization and purification treatment. The carbon fibers between adjacent carbon fiber hard felt blocks are cut and misaligned with each other, and the resin includes phenolic resin, epoxy resin, furan resin, urea-formaldehyde resin, and vinyl resin; the outer thermal insulation body includes several layers of carbon felt wound around the outside of the intermediate body, and carbon ropes for binding and fixing the carbon felt.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, it also includes a level meter arranged in the topmost crucible of the crucible group for detecting the thickness of the graphitized material, and a PLC or an industrial computer is electrically connected to the level meter and the feeding mechanism to control the feeding amount of the feeding mechanism.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, the discharging mechanism is a discharging screw conveyor, and the cooler has a water cooling jacket, and a water inlet pipe and a water outlet pipe connected to the water cooling jacket.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, the discharge mechanism is connected to a storage bin, a discharge port is provided at the bottom of the cooler, and the discharge mechanism is connected to the discharge port through a pipeline.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, a sealing mechanism is provided at the connection between the upper and lower adjacent bottomless crucibles, and the sealing mechanism includes at least one annular groove on the convex stop, a soft felt layer arranged between the outer side surface of the convex stop and the inner side surface of the concave stop, and graphite powder and resin glue solidified layers respectively arranged between the end face of the convex stop and the bottom face of the concave stop, and between the bottom face of the convex stop and the end face of the concave stop; the annular groove is also provided with a graphite rope for tying the soft felt layer to the annular groove of the convex stop.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, it also includes an adaptive protection device, which includes a single call valve connected to the vertical furnace body 1, a pressure relief pipe connected to the single call valve, the outlet end of the pressure relief pipe is connected to a water reservoir, a water supply pipe for supplying water to the water reservoir, a water replenishment valve connected to the water supply pipe, and an overflow pipe connected to the water reservoir; the outlet end of the pressure relief pipe is inserted below the water surface of the water reservoir.

On the basis of the above-mentioned improvement scheme, as a further improved technical scheme, the water level of the water reservoir is lower than the outlet position of the single call valve, and the pressure relief pipe has an inclined section or a vertical section; the inclined section or the vertical section of the pressure relief pipe can accommodate a water volume that is not less than the water storage volume of the water reservoir above the outlet end of the pressure relief pipe.

On the basis of the above improvement scheme, as a further improvement technical scheme, the last section of the pressure relief pipe is an inclined section.

An intelligent protection device for a continuous graphitization and purification furnace includes an explosion relief pipe, a spray tower and a fire water supply system; wherein:

One end of the explosion relief pipe is connected to the vertical furnace body of the continuous graphitization and purification furnace, and the other end is connected to the spray tower. An explosion-proof plate is provided at the inlet of the explosion relief pipe, and an anti-reverse mechanism is provided at the outlet of the explosion relief pipe. An inert gas thermal nozzle is provided in the explosion relief pipe, and the inert gas thermal nozzle is connected to the inert gas supply pipe.

The spray tower is provided with a thermal nozzle and an atomizing nozzle, the fire water supply system supplies water to the thermal nozzle and the atomizing nozzle, and the water supply pipeline of the fire water supply system is provided with a control valve for controlling the water inlet of the atomizing nozzle;

The explosion-venting pipeline is also connected to a dry powder explosion suppression system, which includes a pressure sensor for measuring the pressure inside the explosion-venting pipeline and/or a flame monitoring sensor for monitoring the flame condition inside the explosion-venting pipeline, a dry powder explosion suppressor connected to the explosion-venting pipeline, and a controller for controlling the opening and closing of the dry powder explosion suppressor. The pressure sensor and/or the flame monitoring sensor are electrically connected to the controller; the controller is also electrically connected to the control valve.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, the fire water supply system is a fire gas top pressure water supply system.

On the basis of the above improvement scheme, as a further improvement technical scheme, a wire mesh is provided on the top of the spray tower.

On the basis of the above improvement scheme, as a further improvement technical scheme, a lightning rod is provided on the top of the spray tower.

On the basis of the above improvement scheme, as a further improvement technical scheme, the inert gas thermal nozzle, thermal nozzle and atomizing nozzle are all 90° solid cone nozzles.

On the basis of the above-mentioned improvement scheme, as a further improved technical scheme, the anti-reverse series mechanism is a self-weight sealing cover, which is hinged to the explosion-relief pipe through a hinge, and a soft felt seal is provided between the end of the explosion-relief pipe near the self-weight sealing cover and the self-weight sealing cover. When the pressure value in the explosion-relief pipe is higher than the set value, the anti-reverse series mechanism opens, and when the pressure is lower than the set value, the anti-reverse series mechanism is closed.

A cooling system for a continuous graphitization and purification furnace, comprising a heat exchange mechanism for cooling various parts of the continuous graphitization and purification furnace, a cooling tower connected to a water outlet of the heat exchange mechanism, a water tank connected to the cooling tower, a first water pump whose water inlet is connected to the water tank and whose water outlet is connected to a water inlet of the heat exchange mechanism, and a second water pump connected in parallel with the first water pump; a third water pump connected in parallel with the first water pump and the second water pump, a first control valve arranged on an inlet pipe of the first water pump, a second control valve and a first pressure sensor arranged on an outlet pipe of the first water pump, a third control valve arranged on an inlet pipe of the second water pump, and a pressure sensor arranged on an outlet pipe of the second water pump. a fourth control valve and a second pressure sensor arranged on the heat exchange mechanism, a fifth control valve arranged on the inlet pipe of the third water pump, a sixth control valve and a third pressure sensor arranged on the outlet pipe of the third water pump, a flow sensor, a fourth pressure sensor and a one-way valve arranged on the main water inlet pipe of the heat exchange mechanism, and a controller electrically connected to the first control valve, the second control valve, the third control valve, the fourth control valve, the fifth control valve, the sixth control valve, the first water pump, the second water pump, the third water pump, the first pressure sensor, the second pressure sensor, the third pressure sensor and the fourth pressure sensor; the first water pump and the second water pump are powered by a first power supply, and the third water pump is powered by a second power supply.

On the basis of the above-mentioned improvement scheme, as a further improvement technical scheme, the graphitization furnace comprises an upper cover, a cylinder, a lower cover, an induction coil and a cooler; the heat exchange mechanism comprises mechanisms for cooling and exchanging heat for the upper cover, the cylinder, the lower cover, the induction coil and the cooler respectively, the mechanism for cooling and exchanging heat for the cylinder comprises a first cooling jacket, and the mechanism for cooling and exchanging heat for the lower cover comprises a second cooling jacket.

On the basis of the above improvement scheme, as a further improvement technical scheme, spiral guide plates are provided in both the first cooling jacket and the second cooling jacket.

In the technical solution provided by the present invention, the graphitized material undergoes three stages of preheating and exhaust, heat preservation and graphitization, and cooling and discharging during the flow in the bottomless crucible and the cooler, thereby realizing continuous production of the graphitization process, and having a stable temperature field in the continuous graphitization and purification furnace, thereby improving production efficiency and product quality; there is upper and lower stirring in the crucible, wherein the upper stirring is mainly for accelerating the preheating of the graphitized material and unobstructed exhaust, and the lower stirring is mainly for exhaust and accelerating the cooling of the graphitized material; by adjusting the discharge amount of the discharging mechanism, the time of the graphitization process can be conveniently controlled, thereby improving the quality of the product and balancing production. It is suitable for use with a maximum temperature between 2000°C and 3150°C to meet different graphitization degrees or purification purity requirements.

In the technical solution provided by the present invention, when the pressure in the graphitization furnace increases to the opening pressure set by the single-call valve 2, the single-call valve opens, and the graphitization furnace is depressurized through the single-call valve and the pressure relief pipe, and the materials discharged from the graphitization furnace enter the water reservoir, which can effectively avoid the pollution of the environment by dust, causing secondary hazards such as short circuit and fire to electrical components, and can also effectively avoid the harm of dust to people. The single-call valve belongs to the mechanical opening method, and the protective device does not have a complex control system. It can effectively prevent the hazards caused by misoperation or sensor delay and damage triggering. It can also open normally in the absence of power, which improves the stability of the system, greatly improves the safety and stability of the operation of the graphitization furnace, and avoids the occurrence of safety accidents and secondary accidents.

In the technical solution provided by the present invention, the explosion-proof disk, the thermal nozzle, and the inert gas thermal nozzle are mechanically opened, which can effectively prevent the hazards caused by misoperation or sensor delay or damage triggering, greatly improve the safety and stability of the graphitization furnace, and provide pressure relief, cooling, and inert environment protection in time in unexpected emergency situations to avoid the occurrence of safety accidents and secondary accidents.

In the technical solution provided by the present invention, the graphitization furnace cooling system adopts three water pumps connected in parallel to supply circulating cooling water, and one of the three water pumps is powered by a second power supply, which can improve the safety and stability of the operation of the graphitization furnace cooling system.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

FIG1 is a schematic diagram of the structure of a continuous graphitization and purification furnace in an embodiment;

FIG2 is a schematic diagram of the cross-sectional structure of the thermal insulation layer in the embodiment;

FIG3 is an enlarged view of portion A of FIG2 ;

Figure 4 is a schematic diagram of the connection structure of upper and lower adjacent bottomless crucibles in an embodiment;

Figure 5 is an enlarged view of part I of Figure 4;

FIG6 is a schematic diagram of the front view of the structure when the soft felt layer in the embodiment is unfolded;

FIG7 is a schematic diagram of a top view of the structure when the soft felt layer in the embodiment is unfolded;

Figure 8 is a schematic diagram of the partial structure of the cooler in the embodiment;

FIG. 9 is a schematic diagram of a partial top view of the cooler in the embodiment.

FIG. 10 is a schematic diagram of the structure of an adaptive protection device for a continuous graphitization and purification furnace.

FIG. 11 is a schematic diagram of the structure of the intelligent protection device in the embodiment.

FIG. 12 is a schematic diagram of the front view of the cooling system of the graphitization furnace according to an embodiment.

FIG. 13 is a schematic diagram of the front structural view of the cooling jacket in the embodiment.

Implementation

The present invention will be further described below in conjunction with the accompanying drawings.

The continuous graphitization and purification furnace (hereinafter also referred to as continuous graphitization furnace, graphitization furnace, purification furnace) as shown in FIG1 includes:

A vertical furnace body 1 having a cavity inside, and an inert gas pipe 24 communicating with the cavity for providing a protective atmosphere;

A feeding mechanism 5 and an exhaust pipe 9 connected to the top of the vertical furnace body 1;

An induction coil 2 is arranged in the vertical furnace body 1 and extends upward from the bottom of the vertical furnace body 1. The core of the induction coil 2 is provided with a crucible group consisting of a plurality of coaxial vertically stacked bottomless crucibles 3. A heat-insulating layer 4 is provided between the crucible group 3 and the induction coil 2.

A first driving device 6 is arranged at the top of the vertical furnace body 1, and a first graphite shaft 7 is transmission-connected to the first driving device 6, an upper stirring blade 8 is connected to the first graphite shaft 7, the first graphite shaft 7 extends from the top of the vertical furnace body 1 into the bottomless crucible 3 at the upper part of the crucible group, and the upper stirring blade 8 is used to stir the material;

A cooler 10 is connected to the discharge port at the bottom end of the vertical furnace body 1. The bottom of the cooler 10 is connected to a second driving device 11. The second driving device 11 is connected to a second graphite shaft 12 in a transmission manner. A lower stirring blade 13 is connected to the second graphite shaft 12. The second graphite shaft 12 extends from the bottom of the cooler 10 into the cooler 10 and extends to the bottomless crucible 3 at the bottom of the crucible group. The lower stirring blade 13 is used to stir the material.

A discharging mechanism 14 disposed below the cooler 10;

A plurality of temperature measuring channels 17 pass through the induction coil 2 and the insulation layer 4 and directly reach the crucible group. Infrared thermometers 18 are provided in the temperature measuring channels 17.

On the basis of the above basic scheme, as one of the embodiments, preferably, the upper and lower adjacent bottomless crucibles 3 are connected by a convex stopper 19 and a concave stopper 20 respectively arranged on the upper and lower adjacent bottomless crucibles 3 .

As shown in Figures 4 and 5, the continuous graphitization and purification furnace provided by the present invention has a sealing mechanism at the stopper connection between the bottomless crucibles, and the sealing mechanism includes at least two annular grooves 27 provided on the convex stopper 19, a soft felt layer 28 arranged between the outer side surface of the convex stopper 19 and the inner side surface of the concave stopper 20, and a graphite powder and resin glue solidified layer 29 respectively arranged between the end surface of the convex stopper 19 and the bottom surface of the concave stopper 20 and between the bottom surface of the convex stopper 19 and the end surface of the concave stopper 20, located at the annular groove 27, tying the soft felt layer The sealing mechanism is made by the following process, as shown in Figures 6 and 7, the soft felt is cut into a suitable width, L-shaped joint surfaces are respectively provided at the overlaps of the two ends of the soft felt, the soft felt is wrapped on the convex stop 19 and then tied with the graphite rope 30, the graphite powder and resin glue are mixed evenly, and then applied to the end surface and bottom surface of the concave stop 20 respectively, the convex stop 19 wrapped with the soft felt is inserted into the concave stop 20, the bottomless crucible is stacked and assembled, the axis is aligned, and it is placed in an industrial oven for baking, the baking temperature is 200-250°C, and the time is not less than 24 hours. The depth of the annular groove 27 is adapted to the diameter of the graphite rope 30.

At present, the sealing between crucibles is achieved by fine machining the joint surface to improve the matching accuracy between the crucibles. Because there is often a certain pressure difference between the inside and outside of the crucible, the reliability of the joint surface sealing method is low, which is easy to cause the materials inside and outside the crucible to cross each other, affecting the purity of the graphitized material in the crucible. After being processed by the above technical solution, even if there is a certain pressure difference inside and outside the bottomless crucible, the stop connection between the bottomless crucibles will not leak. After the resin glue in the graphite powder is graphitized at high temperature in the graphitization furnace, the carbon element therein may be graphitized, and other substances will evaporate. The soft felt layer 27, the graphite rope 29, and the graphite powder are all resistant to high temperatures and are not easy to damage. It can improve the sealing reliability between the bottomless crucibles in the continuous graphitization and purification furnace, avoid the materials inside and outside the bottomless crucible from crossing each other, and improve the purity of the graphitized materials produced by the continuous graphitization and purification furnace.

As shown in FIG1 , the furnace body 1 includes a cylinder, an upper cover 25 connected to the upper end of the cylinder, and a lower cover 26 connected to the lower end of the cylinder. The cylinder, the upper cover 25 and the lower cover 26 are the main supporting parts of the equipment, and their shapes and sizes can be selected and designed according to actual needs. As one embodiment, the cylinder is a cylindrical cylinder, and the upper cover 25 and the lower cover 26 are selected in the shape of a head. The cylindrical cylinder, the upper cover 25, the lower cover 26 and the cooler 10 are all sandwich structures, equipped with cooling water, to meet the requirements of continuous production for equipment cooling. The induction coil 2 is annularly located on the lower cover 26.

As shown in Figures 4 and 5, the upper and lower bottomless crucibles 3 are connected by stoppers. The bottomless crucibles 3 are coaxial when stacked and can be stacked to a corresponding height as required. The stacking of multiple bottomless crucibles 3 can simultaneously meet the requirements of bottomless crucible manufacturing, equipment capacity and the residence time of materials in the furnace during the graphitization process. The stacked bottomless crucibles 3 are located at the core of the induction coil 2 and on the upward extension line of the core of the induction coil 2. There is a heat preservation cavity between the bottomless crucible 3 and the induction coil 2, and the heat preservation cavity is filled with a heat preservation layer 4.

As shown in FIG1 , the first drive device 6 can be a common structure of a motor driving a reducer. The first drive device 6 is connected to the first graphite shaft 7 by transmission. The upper stirring blade 8 is connected to the first graphite shaft 7. The first drive device 6 drives the upper stirring blade 8 to rotate through the first graphite shaft 7 to stir the material in the upper bottomless crucible 3, so that the graphitized material is heated evenly during the preheating process, achieving the purpose of uniform temperature rise, and at the same time, it is conducive to the escape of the volatilized gas. The second drive device 11 can be a common structure of a motor driving a reducer. The second drive device 11 is connected to the second graphite shaft 12 by transmission. The lower stirring blade 13 is connected to the second graphite shaft 12. The second drive device 11 drives the lower stirring blade 13 to rotate through the second graphite shaft 12 to stir the material in the lower bottomless crucible 3, so that the graphitized material can continuously contact the cooler 10 during the cooling process, and achieve the purpose of uniform cooling.

As shown in FIG1 , there are several temperature measurement channels 17 in the upper, middle and lower parts of the induction coil 2 and the insulation layer 4. The maximum temperature of the bottomless crucible can reach more than 2800 degrees Celsius during operation. There are multiple temperature measurement channels 17 that pass through the induction coil 2 and the insulation layer 4 to directly reach the outer surface of the bottomless crucible 3. Multiple infrared thermometers 18 can detect the temperature of the bottomless crucible by scanning the bottomless crucible through the temperature measurement channels. The infrared thermometer 18 has high temperature and low temperature. A low temperature infrared thermometer is used within 1200 degrees Celsius, and a high temperature infrared thermometer is used above 1200 degrees Celsius to ensure the accuracy of temperature monitoring during the heating process.

As shown in FIG. 1 , as one embodiment thereof, the feeding mechanism 5 has a powder bin and a flow control valve connected to the discharge port of the powder bin, and the powder falls from the powder bin through the flow control valve into the bottomless crucible by its own weight.

As shown in Figures 1, 8 and 9, the top of the cooler 10 is connected to the lower cover 26, and the bottom of the cooler 10 is a gradually shrinking inclined structure. In the axial direction of the cooler 10, a shaft sleeve connected to the inclined surface is provided, and the second driving device 11 is connected to the lower end of the shaft sleeve. The second graphite shaft 12 passes through the shaft sleeve and is transmission-connected to the second driving device 11. The discharging mechanism 14 is connected to the bottom of the cooler 10. The discharging mechanism 14 controls the flow rate of the material in the bottomless crucible 3 and the cooler 10, maintains the graphitization reaction time, and realizes continuous discharging.

During operation, the graphitized material enters the upper part of the bottomless crucible through the feeding mechanism 5, and the graphitized material in the upper part of the bottomless crucible is stirred by the upper stirring blade 8, so that the graphitized material is evenly preheated in the upper part of the bottomless crucible and the volatile substances are discharged. After the volatile substances gather in the cavity above the bottomless crucible, they are discharged through the exhaust pipe 9. The inert gas pipe 16 introduces protective gas into the continuous graphitization and purification furnace to maintain a positive pressure and protective atmosphere in the continuous graphitization and purification furnace. The graphitized material passes through the upper, middle and lower parts of the bottomless crucible and gradually falls into the cooler 10 by gravity. After being cooled by the cooler 10, it enters the storage bin 15 through the discharging mechanism 14. During the flow of the graphitized material in the bottomless crucible, it goes through three stages: preheating and exhaust, heat preservation and graphitization, and cooling and discharging, thus realizing the continuous production of the graphitization and purification process and improving the production efficiency.

On the basis of the above basic scheme, as one of the embodiments, as shown in FIG. 2 and FIG. 3 , the continuous graphitization and purification furnace provided by the present invention, the thermal insulation layer 4 includes an inner frame body 21 , an intermediate body 22 and an outer thermal insulation body 23 . The inner frame body 21 is made of a three-dimensional needle-punched carbon fiber blank, which is shaped and introduced with a carbon source gas for chemical vapor deposition to densify to 1.4g/cm3~1.6g/cm3 to prepare a carbon/carbon composite material, and then the carbon/carbon composite material is graphitized at a temperature of 1800~2500°C under the protection of an inert gas or nitrogen to obtain the carbon/carbon composite material; the intermediate body 22 includes at least one layer of carbon fiber hard felt layer formed by splicing a plurality of carbon fiber hard felt blocks, the carbon fiber hard felt blocks are composed of a plurality of layers of carbon fiber carbon felt and resin is brushed or sprayed between the carbon fiber carbon felt layers, and after curing and shaping, carbonization and purification treatment, the formed carbon fiber hard felt is cut into a plurality of blocks, the carbon fibers between adjacent carbon fiber hard felt blocks are cut off and are mutually dislocated, and the resin includes phenolic resin, epoxy resin, furan resin, urea-formaldehyde resin, and vinyl resin; the outer thermal insulation body 23 includes a plurality of layers of carbon felt wrapped around the outside of the intermediate body, and a carbon rope for binding and fixing the carbon felt.

In the above technical solution, the insulation material wrapped around the outside of the bottomless crucible 3 is a three-dimensional needle-punched carbon fiber composite material. After chemical vapor deposition, the density of the three-dimensional needle-punched carbon fiber is increased from 0.5g/cm3 to 1.4g/cm3~1.6g/cm3. After graphitization treatment at a temperature of 1800~2500℃ and under the protection of inert gas or nitrogen, it has anti-oxidation, anti-corrosion and heat insulation functions. Because the inner frame body 21 is an integral structure and has uniform heat conduction, it is beneficial for the thermal field in the bottomless crucible 3 to reach a uniform temperature. The intermediate 22 uses a carbon fiber hard felt spliced from a number of carbon fiber hard felt blocks. The adjacent carbon fiber hard felt blocks are spliced. Because the carbon fibers are cut, the carbon fibers between the adjacent carbon fiber hard felt blocks are mutually misaligned. When multiple blocks are combined, the probability that the carbon fibers can be connected to each other into a ring is greatly reduced. The carbon fibers as conductors are not connected into a ring, and will not induce heat in an electromagnetic environment, thereby greatly reducing the induced self-heating in an electromagnetic environment. The use of carbon fiber hard felt can improve the rigidity of the insulation layer. The carbon fiber felt has a low density and plays a good role in thermal insulation. The carbonization temperature of the carbon fiber felt is 600~1200℃, and the purification temperature is 1600~2400℃. The carbonization and purification processes are carried out in an argon or nitrogen atmosphere. After the carbon fiber felt is purified by high-temperature heat treatment, the impurity content is reduced, thereby reducing the conductivity and reducing the induced self-heating in an electromagnetic environment. The outer insulation body 23 is formed by winding multiple layers of carbon felt and is located in the outermost layer. The intensity of electromagnetic induction self-heating has been greatly reduced, but it can provide a good insulation effect. The inner frame body 21, the intermediate body 22 and the outer insulation body 23 are combined with each other, their functions are complementary and synergistic, so that the insulation layer 4 has excellent performance.

On the basis of the above basic scheme, as one of the embodiments, as shown in FIG1 , the continuous graphitization and purification furnace provided by the present invention further includes a material level meter 16 for detecting the height of the graphitized material in the bottomless crucible, a PLC or industrial computer electrically connected to the material level meter 16, and the PLC or industrial computer is electrically controlled and connected to the feeding mechanism 5 to control the feeding amount of the feeding mechanism 5. The purpose of stabilizing the feeding and stabilizing the operation of the continuous graphitization and purification furnace is achieved.

Based on the above basic scheme, as one embodiment thereof, the discharging mechanism (14) is a discharging screw conveyor, and the cooler (10) has a water cooling jacket, and a water inlet pipe and a water outlet pipe connected to the water cooling jacket. As shown in FIG1 , the continuous graphitization and purification furnace provided by the present invention, the cooler 10 has a water cooling jacket, and a water inlet pipe and a water outlet pipe connected to the water cooling jacket. Cooling water is passed into the water cooling jacket to cool the material.

As shown in FIG10, the adaptive protection device of the continuous graphitization and purification furnace comprises a single-call valve 2a connected to the vertical furnace body 1 of the continuous graphitization and purification furnace, a pressure relief pipe 3a connected to the outlet end of the single-call valve 2a, a water reservoir 4a connected to the outlet end of the pressure relief pipe 3a, a water supply pipe for supplying water to the water reservoir 4a, a water replenishment valve 5a connected to the water supply pipe, and an overflow pipe 6a connected to the water reservoir 4a; the outlet end of the pressure relief pipe 3a is inserted below the water surface of the water reservoir 4a. The installation position of the water reservoir 4a is lower than the outlet installation position of the single-call valve 2a, and the pressure relief pipe 3a has an inclined section or a vertical section; the amount of water that the inclined section of the pressure relief pipe 3a can accommodate is not less than the amount of water stored in the water reservoir 4a above the outlet end of the pressure relief pipe 3a.

When the water level in the water reservoir 4a drops, the water replenishment valve 5a opens to replenish water. The water replenishment valve 5a can be an automatic valve, such as a float valve, a regulating valve with liquid level control, or a manual valve. The water replenishment valve 5a can ensure that the water level in the water reservoir 4a is at a normal level; when too much water is injected into the water reservoir 4a, the excess water is discharged from the overflow pipe 6a, which can ensure that the water level in the water reservoir 4a is at a normal level, and prevent the water in the water reservoir 4a from flowing back into the pressure relief pipe 3a due to the rising water level and increased pressure.

During the operation of the graphitization furnace, the pressure stabilization system of the graphitization furnace fails due to unexpected reasons. When the pressure in the graphitization furnace increases to the opening pressure set by the single-call valve 2a, the single-call valve 2a automatically opens, and the graphitization furnace 1 is depressurized through the single-call valve 2a and the pressure relief pipe 3a. The material in the graphitization furnace 1 enters the water reservoir 4a, so that the pressure in the graphitization furnace 1 is reduced, and the safe operation of the graphitization furnace 1 is maintained. When the single-call valve 3 is opened, the material discharged from the graphitization furnace 1 is high in temperature and accompanied by dust. When discharged into the water reservoir 4a, the discharge is cooled and mixed with water and then precipitated, and the gas is discharged upward, which can effectively avoid dust pollution to the environment, bring about secondary hazards such as short circuit and fire to electrical components, and avoid dust harm to people. When the water level of the water reservoir 4a rises, the excess water after the water level rises is discharged through the overflow pipe 6a. The graphitization furnace can provide buffer time for eliminating production failures through pressure relief, and avoid more serious safety accidents.

In the present technical solution, when the pressure in the graphitization furnace increases to the opening pressure set by the single-call valve 2a, the single-call valve 2a opens, and the graphitization furnace is depressurized through the single-call valve 2a and the pressure relief pipe 3a, and the material discharged from the graphitization furnace 1 enters the water reservoir 4a, which can effectively avoid dust pollution to the environment, secondary hazards such as short circuit and fire to electrical components, and avoid dust damage to people.

The single-call valve is mechanically opened, and the protective device does not have a complex control system. It can effectively prevent the hazards caused by misoperation or sensor delay or damage triggering. It can also open normally in the absence of power, which improves the stability of the system and greatly improves the safety and stability of the graphitization furnace operation, avoiding safety accidents and secondary accidents.

Please refer to FIG. 11 , the intelligent protection device of the continuous graphitization and purification furnace includes an explosion relief pipe 2b, a spray tower 4b and a fire water supply system 8b; wherein,

One end of the explosion relief pipe 2b is connected to the vertical furnace body 1 of the continuous graphitization and purification furnace, and the other end is connected to the spray tower 4b. An explosion-proof plate 3b is provided at the inlet of the explosion relief pipe 2b, and an anti-reverse mechanism 5b is provided at the outlet of the explosion relief pipe 2b. An inert gas thermal nozzle 10b is provided in the explosion relief pipe 2b, and the inert gas thermal nozzle 10b is connected to the inert gas supply pipe.

The spray tower 4b is provided with a thermal nozzle 6b and an atomizing nozzle 7b, and a fire water supply system 8b supplies water to the thermal nozzle 6b and the atomizing nozzle 7b. A control valve 9b for controlling the water inlet of the atomizing nozzle 7b is provided on the water supply pipeline of the fire water supply system 8b;

The explosion-proof pipe 2b is also connected to a dry powder explosion suppression system 11b, which includes a pressure sensor for measuring the pressure inside the explosion-proof pipe 2b and/or a flame monitoring sensor for monitoring the flame condition inside the explosion-proof pipe 2b, a dry powder explosion suppressor connected to the explosion-proof pipe 2b, and a controller for controlling the opening and closing of the dry powder explosion suppressor. The pressure sensor and/or the flame monitoring sensor are electrically connected to the controller; the controller is also electrically connected to the control valve 9b, and the controller can be a PLC, an industrial computer, etc.

In one embodiment, the inert gas thermal nozzle 10b is arranged at one end of the explosion-proof plate 3b near the explosion-proof pipe 2b. The inert gas thermal nozzle 10b is a 90° solid cone nozzle made of 310S stainless steel, and the glass bead destruction temperature at the front end of the nozzle is 80°C. The thermal nozzle 6b is a 90° solid cone nozzle made of 310S stainless steel, and the glass bead destruction temperature at the front end of the nozzle is 80°C. The atomizing nozzle 7b is a 90° solid cone nozzle made of 310S stainless steel. The dry powder explosion suppression system 11b is arranged at two-thirds of the explosion-proof pipe 2b. When the high-temperature material passes through the position of the dry powder explosion suppression system 11b, the dry powder explosion suppression system 11b is opened, and the dry powder is sprayed into the pipe to suppress and cool the explosion-proof pipe 2b. The fire-fighting water supply system 8b adopts a fire-fighting gas top-pressure water supply system. The fire-fighting gas top-pressure water supply system includes components such as a pressure water tank, a control cabinet, a top-pressure gas storage system, and a pressure reduction release device. In the fire-fighting state, compressed gas is filled into the pressure water tank to displace the fire-fighting water in the tank. It can always maintain the fire-fighting rated working pressure in the water supply pipeline and is not easily affected by power outages and gas outages.

During the operation of the graphitization furnace, when the graphitization furnace 1 fails to maintain its voltage stabilization system due to water leakage or material blockage, when the pressure in the graphitization furnace 1 reaches the bursting pressure of the explosion-proof disc 3b, the explosion-proof disc 3b bursts, and the graphitization furnace 1 is depressurized through the explosion-proof disc 3b, the explosion-relief pipe 2b and the anti-reverse mechanism 5b, and the material in the graphitization furnace 1 enters the spray tower 4b. After the explosion-proof disc 3b bursts, the temperature in the explosion-relief pipe 2b reaches the opening temperature of the inert gas thermal nozzle 10b, and the inert gas thermal nozzle 10b opens to spray inert gas into the explosion-relief pipe 2b. When the temperature in the spray tower 4b reaches the opening temperature of the thermal nozzle 6b, the thermal nozzle 6b opens, and the fire water supply system 8b sprays water to the spray tower 4b through the thermal nozzle 6b. When the pressure sensor detects that the pressure in the explosion-proof pipe 2b increases, or/and the flame monitoring sensor detects that there is a flame in the explosion-proof pipe 2b, the pressure sensor or the flame monitoring sensor sends an instruction to the controller to start the dry powder explosion suppressor, and the dry powder explosion suppressor is turned on; when the controller sends an instruction to start the dry powder explosion suppressor, the controller also sends an opening instruction to the control valve 9b. After the control valve 9b is opened, water is sprayed into the spray tower 4b through the atomizing nozzle 7b.

When the explosion-proof plate 3b explodes, the graphitization furnace 1 is directly connected to the explosion-proof pipe 2b, and the high-temperature materials and pressure in the furnace are released through the explosion-proof pipe 2b. After the high-temperature materials in the furnace enter the explosion-proof pipe 2b, the temperature in the explosion-proof pipe 2b exceeds the glass bead destruction temperature of the inert gas thermal nozzle 10b, and the glass beads at the front end of the inert gas thermal nozzle 10b explode. The inert gas pipeline connected to the inert gas thermal nozzle 10b is normally open. At this time, the inert gas cools the explosion-proof pipe 2b through the inert gas thermal nozzle 10b to prevent oxygen from entering the graphitization furnace 1, and at the same time provides an inert gas inert protection environment to prevent fire.

As one embodiment, an anti-reverse mechanism 5b is arranged between the explosion relief pipe 2b and the spray tower 4b. The anti-reverse mechanism 5b is preferably a self-weight sealing cover. The self-weight sealing cover is hingedly connected to the explosion relief pipe 2b. The automatic opening pressure value of the anti-reverse mechanism 5b is designed to be 5MPa (or other design values). A soft felt seal is arranged between the end of the explosion relief pipe 2b near the self-weight sealing cover and the self-weight sealing cover. When the pressure value in the explosion relief pipe 2b is higher than the automatic opening pressure value of the self-weight sealing cover, the self-weight sealing cover is opened. When the explosion-proof plate 3b explodes, the pressure in the explosion relief pipe 2b will be greater than the automatic opening pressure value of the self-weight sealing cover. The self-weight sealing cover is opened. When the pressure in the furnace is released to a value lower than the automatic opening pressure value of the self-weight sealing cover, the self-weight sealing cover is closed by its own gravity to prevent external materials and gases from entering the vertical furnace body 1 of the graphitization furnace, thereby protecting the graphitization furnace 1. The anti-reverse mechanism 5b has waterproof, fireproof and gas reverse function.

The technical solution provided by the present invention is that when the pressure in the graphitization furnace 1 reaches the bursting pressure of the explosion-proof plate 3b, the explosion-proof plate 3b explodes and the pressure is released through the explosion-proof pipe 2b. At this time, the inert gas thermal nozzle 6b, the anti-reverse mechanism 5b and the thermal nozzle 6b are automatically opened. When the pressure sensor detects that the pressure in the explosion-proof pipe increases, or/and the flame monitoring sensor detects that there is a flame in the explosion-proof pipe, the pressure sensor or/and the flame monitoring sensor sends a detection signal to the controller of the dry powder explosion suppression system 11b, and the controller sends a signal to start the dry powder explosion suppressor and the control valve 9b. The dry powder explosion suppressor is turned on to spray dry powder into the explosion-proof pipe, and the control valve 9b turns on the atomizing nozzle 7b to spray water mist into the tower. The inert gas enters the explosion-proof pipe 2b through the inert gas thermal nozzle 10b to cool the high-temperature material and provide an inert gas protection environment to prevent fire. After the explosion-proof disc 3b is destroyed, when the pressure in the graphitization furnace 1 is released to a certain extent, the anti-reverse flow mechanism 5b is closed by its own gravity to prevent external materials and air from entering the graphitization furnace 1, thereby protecting the graphitization furnace 1. The explosion-proof disc 3b, the anti-reverse flow mechanism 5b, the inert gas thermal nozzle 6b, and the thermal nozzle 6b are all automatic opening mechanisms without a complex electrical control system. They can be opened normally even in the absence of power, thereby improving the stability of the system.

As one of the embodiments, four groups of thermal nozzles 6b are provided on the upper part of the spray tower 4b. The thermal nozzles 6b adopt solid cone spray nozzles. The glass bead destruction temperature of the thermal nozzles 6b (the opening temperature of the thermal nozzles 6b) is 80°C. The fire water supply system 8b connected to the pipe where the thermal nozzles 6b are installed is a fire gas top pressure water supply system, which is a normally open system. The pipe where the thermal nozzles 6b are installed maintains a water pressure of about 1 MPa. When the high-temperature material in the explosion-proof pipe 2b reaches the spray tower 4b, the glass beads at the front end of the thermal nozzles 6b explode and spray the high-temperature material to achieve cooling and explosion-proof effects. The gas generated during the spray cooling of the high-temperature material is discharged from the top of the spray tower 4b, and the cooled high-temperature material falls into the bottom of the spray tower 4b.

As one of the embodiments, four groups of atomizing nozzles 7b are provided in the middle of the spray tower 4b. The atomizing nozzles 7b adopt solid cone spray nozzles. The atomizing nozzles 7b are connected to the fire water supply system 8b through a pipeline. Two groups of electromagnetic control valves 9b are provided in parallel on the pipeline. The two groups of control valves 9b are one for use and one for backup. The fire water supply system 8b connected to the control valve 9b pipeline is a fire gas top pressure water supply system, which is a normally open system. The water pressure of about 1MPa is continuously maintained in the pipeline. When the pressure sensor detects that the pressure in the explosion relief pipeline increases, or/and the flame monitoring sensor detects that there is a flame in the explosion relief pipeline, the pressure sensor or the flame monitoring sensor sends an instruction to the controller to start the dry powder explosion suppressor, and the dry powder explosion suppressor is turned on; when the dry powder explosion suppressor is turned on, the controller sends an opening instruction to the control valve 9b. After the control valve 9b is opened, water is sprayed into the spray tower 4b through the atomizing nozzle 7b to spray and cool the material in the spray tower 4b. After the high-temperature material is sprayed and cooled by the four groups of thermal nozzles 6b, it is further sprayed and cooled by the four groups of atomizing nozzles 7b until the material falls into the bottom of the tower.

As one of the embodiments, a layer of wire mesh 12b is provided on the top of the spray tower 4b to prevent foreign objects from falling into the tower without affecting the air leakage. A lightning rod 13b is provided on the top of the spray tower to connect with the workshop lightning protection system to play a lightning protection role.

The continuous graphitization and purification furnace cooling system as shown in Figures 12 to 13 includes a heat exchange mechanism for cooling various parts of the graphitization furnace, a cooling tower 1c connected to a water outlet of the heat exchange mechanism, a water tank 2c connected to the cooling tower 1c, a first water pump 3c whose water inlet is connected to the water tank 2c and whose water outlet is connected to the water inlet of the heat exchange mechanism, a second water pump 4c connected in parallel with the first water pump 3c, a third water pump 5c connected in parallel with the first water pump 3c and the second water pump 4c, a first control valve 6c arranged on the inlet pipe of the first water pump 3c, a second control valve 7c and a first pressure sensor 8c arranged on the outlet pipe of the first water pump 3c, a third control valve 9c arranged on the inlet pipe of the second water pump 4c, a fourth control valve 10c and a second pressure sensor 8c arranged on the outlet pipe of the second water pump 4c a flow sensor 15c, a fourth pressure sensor 16c and a one-way valve 17c arranged on the main water inlet pipe of the heat exchange mechanism; a controller electrically connected to the first control valve 6c, the second control valve 7c, the third control valve 9c, the fourth control valve 10c, the fifth control valve 12c, the sixth control valve 13c, the first water pump 3c, the second water pump 4c, the third water pump 5c, the first pressure sensor 8c, the second pressure sensor 11c, the third pressure sensor 14c and the fourth pressure sensor 16c; the first water pump 3c and the second water pump 4c are powered by a first power supply, and the third water pump 5c is powered by a second power supply.

The graphitization furnace adopts the induction heating method, and the temperature can be raised to 3000 degrees at the highest. The high temperature heats the center of the furnace, but the furnace body needs to be cooled, so the furnace body adopts the water circulation cooling method to make the furnace body temperature not exceed 30 degrees. The cooling water circulation process is: first turn on the first water pump 3c or the second water pump 4c to circulate the circulating cooling water in the pipeline. The cooling water takes away the heat of the graphite furnace body through the heat exchange mechanism that cools various parts of the graphitization furnace, and returns to the water tank 2c for recycling after cooling in the cooling tower 1c. When the circulating water is not enough, water can be added to the cooling tower 1c or the water tank 2c. Under normal circumstances, one of the first water pump 3c and the second water pump 4c is running. At this time, the control valves on the inlet and outlet pipes of the running water pump are opened, and the control valves on the inlet and outlet pipes of the standby pump are closed. The pressure sensor on the outlet pipe of the running water pump and the flow sensor 15c and the fourth pressure sensor 16c on the total water inlet pipe of the heat exchange mechanism all transmit normal information to the PLC. When the running water pump fails, for example, the pressure drops below the set pressure value, and the flow rate drops below the set value, the pressure sensor, flow sensor 15c and fourth pressure sensor 16c on the outlet pipe of the running water pump transmit fault information to the controller (such as PLC), and the controller controls to open the control valves on the inlet pipe and outlet pipe of the standby pump, start the standby pump, close the control valves on the inlet pipe and outlet pipe of the original running water pump, and stop the operation of the original running pump. If there is a sudden power outage or other reasons, the first water pump 3c and the second water pump 4c cannot operate normally, for example, after switching the first water pump 3c or the second water pump 4c to operate, the pressure and flow rate are still lower than the set pressure value or the standby pump cannot be enabled during the switching process, the flow sensor 15c and the fourth pressure sensor 16c transmit fault information to the controller, and the controller (PLC) controls to open the fifth control valve 12c on the inlet pipe of the third water pump 5c and the sixth control valve 13c on the outlet pipe, and start the third water pump 5c, and the third water pump 5c is powered by the second power supply. The second power source includes power from the grid, a charging energy storage power source or a generator set. If it is a generator set, it also includes a controller (PLC) to control the start of the generator set.

When the first water pump 3c and the second water pump 4c of the graphitization furnace cooling system are operating normally, the power is suddenly cut off. When the first water pump 3c and the second water pump 4c cannot operate normally, the first control valve 6c, the second control valve 7c, the third control valve 9c and the fourth control valve 10c are all closed to prevent the cooling water pumped by the third water pump 5c from flowing back into the water tank 2c. The fifth control valve 12c and the sixth control valve 13c are opened, and the third water pump 5c is powered by the second power supply to send the cooling water stored in the water tank 2c into the cooling system, so that the graphitization furnace is slowly cooled down or maintains normal production, ensuring the safety of the equipment and system. The one-way valve 17c prevents the cooling water in the heat exchange mechanism from flowing back to the water tank 2c.

In this technical solution, the graphitization furnace cooling system adopts three water pumps connected in parallel to supply circulating water, and one of the three water pumps is powered by the second power supply, which can improve the safety and stability of the operation of the graphitization furnace cooling system.

As a partial embodiment thereof, as shown in FIG12, the graphitization furnace comprises an upper cover 18c, a cylinder 19c, a lower cover 20c, an induction coil 21c and a cooler 22c; the heat exchange mechanism comprises mechanisms for cooling and exchanging heat for the upper cover 18c, the cylinder 19c, the lower cover 20c, the induction coil 21c and the cooler 22c respectively, the mechanism for cooling and exchanging heat for the cylinder 19c comprises a first cooling jacket 23c, and the mechanism for cooling and exchanging heat for the lower cover 20c comprises a second cooling jacket 24c. A spiral guide plate 25c is provided in both the first cooling jacket 23c and the second cooling jacket 24c.

The present invention is not limited to the above preferred embodiments, and can also be transformed and improved in various forms within the spirit defined in the claims and the specification of the present invention, which can solve the same technical problems and achieve the expected technical effects, so it will not be repeated. All solutions that can be directly or associatively derived from the contents disclosed by ordinary technicians in the field, as long as they are within the spirit defined in the claims, also belong to the protection scope of the present invention.

Claims (19)

A continuous graphitization and purification furnace, characterized in that it comprises: A vertical furnace body having a cavity inside, and an inert gas pipe communicating with the cavity for providing a protective atmosphere; A feeding mechanism and an exhaust duct connected to the top of the vertical furnace body; An induction coil is arranged in the vertical furnace body and extends upward from the bottom of the vertical furnace body, wherein the core of the induction coil is provided with a crucible group consisting of a plurality of coaxial vertically stacked bottomless crucibles, and an insulation layer is provided between the crucible group and the induction coil; A first driving device is arranged at the top of the vertical furnace body, and a first graphite shaft is drivingly connected to the first driving device, an upper stirring blade is connected to the first graphite shaft, the first graphite shaft extends from the top of the vertical furnace body into the bottomless crucible at the top of the crucible group, and the upper stirring blade is used to stir the material; A cooler is connected to the discharge port at the bottom end of the vertical furnace body, the bottom of the cooler is connected to a second driving device, the second driving device is transmission-connected to a second graphite shaft, a lower stirring blade is connected to the second graphite shaft, the second graphite shaft extends from the bottom of the cooler into the cooler and extends to the bottomless crucible at the bottom of the crucible group, and the lower stirring blade is used to stir the material; A discharging mechanism disposed below the cooler; A number of temperature measuring channels pass through the induction coil and the insulation layer and directly reach the crucible group, and infrared thermometers are provided in the temperature measuring channels. The continuous graphitization and purification furnace according to claim 1 is characterized in that the upper and lower adjacent bottomless crucibles are connected by a convex stopper and a concave stopper respectively arranged on the two upper and lower adjacent crucibles. The continuous graphitization and purification furnace according to claim 1 is characterized in that the insulation layer includes an inner frame body, an intermediate body and an outer insulation body; the inner frame body is made of a three-dimensional needle-punched carbon fiber blank, which is shaped and introduced with a carbon source gas for chemical vapor deposition to increase the density to 1.4g/cm3~1.6g/cm3 to prepare a carbon/carbon composite material, and then the carbon/carbon composite material is graphitized at a temperature of 1800~2500℃ under the protection of an inert gas or nitrogen to obtain the obtained product; the intermediate body includes at least one layer composed of several pieces of carbon A carbon fiber hard felt layer formed by splicing fiber hard felt blocks, wherein the carbon fiber hard felt blocks are composed of several layers of carbon fiber carbon felt and resin is brushed or sprayed between the carbon fiber carbon felt layers for solidification and shaping. After carbonization and purification treatment, the formed carbon fiber hard felt is cut into several blocks, and the carbon fibers between adjacent carbon fiber hard felt blocks are cut and misaligned with each other. The resin includes phenolic resin, epoxy resin, furan resin, urea-formaldehyde resin, and vinyl resin; the outer thermal insulation body includes several layers of carbon felt wound around the outside of the intermediate body, and carbon ropes for binding and fixing the carbon felt. The continuous graphitization and purification furnace according to claim 1 is characterized in that it also includes a level meter arranged in the topmost crucible of the crucible group for detecting the thickness of the graphitized material, and a PLC or industrial computer is electrically connected to the level meter and the feeding mechanism to control the feeding amount of the feeding mechanism. The continuous graphitization and purification furnace according to claim 1 is characterized in that the discharging mechanism is a discharging screw conveyor, and the cooler has a water-cooling jacket, and a water inlet pipe and a water outlet pipe connected to the water-cooling jacket. The continuous graphitization and purification furnace according to claim 1 is characterized in that the discharging mechanism is connected to a storage bin, a feeding port is provided at the bottom of the cooler, and the discharging mechanism is connected to the feeding port through a pipeline. The continuous graphitization and purification furnace according to claim 2 is characterized in that a sealing mechanism is provided at the connection between the upper and lower adjacent bottomless crucibles, and the sealing mechanism includes at least one annular groove provided on the convex stop, a soft felt layer arranged between the outer side surface of the convex stop and the inner side surface of the concave stop, and graphite powder and resin glue solidified layers respectively arranged between the end face of the convex stop and the bottom face of the concave stop and between the bottom face of the convex stop and the end face of the concave stop; the annular groove is also provided with a graphite rope for tying the soft felt layer to the annular groove of the convex stop. The continuous graphitization and purification furnace according to claim 1 is characterized in that it also includes an adaptive protection device, which includes a single call valve connected to the vertical furnace body, a pressure relief pipe connected to the single call valve, the outlet end of the pressure relief pipe is connected to a water reservoir, a water supply pipe for supplying water to the water reservoir, a water replenishment valve connected to the water supply pipe, and an overflow pipe connected to the water reservoir; the outlet end of the pressure relief pipe is inserted below the water surface of the water reservoir. The continuous graphitization and purification furnace according to claim 8 is characterized in that the water level of the water reservoir is lower than the outlet position of the single call valve, and the pressure relief pipe has an inclined section or a vertical section; the inclined section or the vertical section of the pressure relief pipe can accommodate a water volume that is not less than the water storage volume of the water reservoir above the outlet end of the pressure relief pipe. The continuous graphitization and purification furnace according to claim 9 is characterized in that the last section of the pressure relief pipe is an inclined section. An intelligent protection device for a continuous graphitization and purification furnace, characterized in that it includes an explosion relief pipe, a spray tower and a fire water supply system; wherein, One end of the explosion relief pipe is connected to the vertical furnace body of the continuous graphitization and purification furnace, and the other end is connected to the spray tower. An explosion-proof plate is provided at the inlet of the explosion relief pipe, and an anti-reverse mechanism is provided at the outlet of the explosion relief pipe. An inert gas thermal nozzle is provided in the explosion relief pipe, and the inert gas thermal nozzle is connected to the inert gas supply pipe. The spray tower is provided with a thermal nozzle and an atomizing nozzle, the fire water supply system supplies water to the thermal nozzle and the atomizing nozzle, and the water supply pipeline of the fire water supply system is provided with a control valve for controlling the water inlet of the atomizing nozzle; The explosion-venting pipeline is also connected to a dry powder explosion suppression system, which includes a pressure sensor for measuring the pressure inside the explosion-venting pipeline and/or a flame monitoring sensor for monitoring the flame condition inside the explosion-venting pipeline, a dry powder explosion suppressor connected to the explosion-venting pipeline, and a controller for controlling the opening and closing of the dry powder explosion suppressor. The pressure sensor and/or the flame monitoring sensor are electrically connected to the controller; the controller is also electrically connected to the control valve. The intelligent protection device for the continuous graphitization and purification furnace according to claim 11 is characterized in that the fire water supply system is a fire gas top pressure water supply system. The intelligent protection device for the continuous graphitization and purification furnace according to claim 11 is characterized in that a wire mesh is provided on the top of the spray tower. The intelligent protection device for the continuous graphitization and purification furnace according to claim 11 is characterized in that a lightning rod is provided at the top of the spray tower. The intelligent protection device for the continuous graphitization and purification furnace according to claim 11 is characterized in that the inert gas thermal nozzle, thermal nozzle and atomizing nozzle are all 90° solid cone nozzles. The intelligent protection device for the continuous graphitization and purification furnace according to claim 11 is characterized in that the anti-reverse flow mechanism is a self-weight sealing cover, which is hinged to the explosion-relief pipe through a hinge, and a soft felt seal is provided between the end of the explosion-relief pipe near the self-weight sealing cover and the self-weight sealing cover, and when the pressure value in the explosion-relief pipe is higher than the set value, the anti-reverse flow mechanism is opened, and when the pressure is lower than the set value, the anti-reverse flow mechanism is closed. A cooling system for a continuous graphitization and purification furnace, comprising a heat exchange mechanism for cooling various parts of the continuous graphitization and purification furnace, a cooling tower connected to a water outlet of the heat exchange mechanism, a water tank connected to the cooling tower, a first water pump whose water inlet is connected to the water tank and whose water outlet is connected to a water inlet of the heat exchange mechanism, and a second water pump connected in parallel with the first water pump; characterized in that it also comprises a third water pump connected in parallel with the first and second water pumps, a first control valve disposed on an inlet pipe of the first water pump, a second control valve and a first pressure sensor disposed on an outlet pipe of the first water pump, a third control valve disposed on an inlet pipe of the second water pump, and a pressure sensor disposed on an outlet pipe of the second water pump. a fourth control valve and a second pressure sensor arranged on the inlet pipe of the third water pump, a fifth control valve arranged on the inlet pipe of the third water pump, a sixth control valve and a third pressure sensor arranged on the outlet pipe of the third water pump, a flow sensor, a fourth pressure sensor and a one-way valve arranged on the main water inlet pipe of the heat exchange mechanism, and a controller electrically connected to the first control valve, the second control valve, the third control valve, the fourth control valve, the fifth control valve, the sixth control valve, the first water pump, the second water pump, the third water pump, the first pressure sensor, the second pressure sensor, the third pressure sensor and the fourth pressure sensor; the first water pump and the second water pump are powered by a first power supply, and the third water pump is powered by a second power supply. The cooling system of the continuous graphitization and purification furnace according to claim 17 is characterized in that the graphitization furnace has an upper cover, a cylinder, a lower cover, an induction coil and a cooler; the heat exchange mechanism includes mechanisms for cooling and exchanging heat with the upper cover, the cylinder, the lower cover, the induction coil and the cooler respectively, the mechanism for cooling and exchanging heat with the cylinder includes a first cooling jacket, and the mechanism for cooling and exchanging heat with the lower cover includes a second cooling jacket. The cooling system of the continuous graphitization and purification furnace according to claim 16 is characterized in that spiral guide plates are provided in the first cooling jacket and the second cooling jacket.